[GHC] #5951: Panic on Malformed instance A => B => C

[GHC]

#5951: Panic on Malformed instance A => B => C
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  Reporter:  br1                       |          Owner:         
      Type:  bug                       |         Status:  closed 
  Priority:  normal                    |      Milestone:  7.6.1  
 Component:  Compiler                  |        Version:  7.4.2  
Resolution:  fixed                     |       Keywords:         
        Os:  Unknown/Multiple          |   Architecture:  x86    
   Failure:  Compile-time crash        |     Difficulty:  Unknown
  Testcase:  rename/should_fail/T5951  |      Blockedby:         
  Blocking:                            |        Related:         
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Comment(by boris):

 I ran into this issue with -> arrows in GHC 7.4.1. Could you please check
 this code in HEAD?


 {{{
 -- no language extensions
 class Clazz a where
   func :: a -> String

 instance Clazz a -> Clazz (Bool -> a) where
   func = undefined
 }}}

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/5951#comment:11>
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